IOSR Journal of Agriculture and Veterinary Science (IOSR-JAVS) e-ISSN: 2319-2380, p-ISSN: 2319-2372. Volume 6, Issue 5 (Nov. - Dec. 2013), PP 22-28 www.iosrjournals.org www.iosrjournals.org 22 | Page Additive Effect of NSP Enzymes and Phytase on Performance, Egg Quality, Nutrient Retention and Gut Health of Laying Hens Fed Corn-Soybean Meal Based Low Energy Diets* J. Narasimha 1 , D. Nagalakshmi 2 , S.T.Viroji Rao 3 and Y. Ramana Reddy 4 1,2,3,4 Department of Animal Nutrition, College of Veterinary Science, Rajendranagar, Sri Venkateswara Veterinary University, Hyderabad, Andhra Pradesh, India-500030. Abstract: A trial was conducted to evaluate pure NSP enzyme combination derived from in vitro studies and commercially available phytase to corn-soybean meal based low energy diets singly and combination of both. The experiment was conducted by using completely randomized design on one hundred and fifty layer birds (40 weeks) of uniform body weight and production with five treatments, six replicates and five hens in each replicate for three laying periods with twenty eight days in each laying period. The performance was measured in terms of egg production, feed intake, weight changes, feed efficiency, egg quality, nutrient retention, and gut health. Egg production improved (P<0.05) with supplementation of phytase alone or in combination of phytase and NSP enzymes. No effect of supplementing NSP enzymes, phytase alone or in combination was observed on feed intake, FCR, egg quality traits and retentions of DM, OM and NFE. Significantly (P<0.05) higher retentions of CP, CF, EE, GE and phosphorus was observed with supplementation of NSP enzymes and similar trend was observed with both NSP and phytase to BD except for phosphorus indicating no associative effect of phytase and NSP enzymes on above nutrient retentions. Intestinal pH, viscosity and E. coli count significantly (P<0.05) reduced with supplementation of NSP enzymes and no further improvement was observed on these variables with supplementation of phytase with NSP enzymes. Gut histology revealed broad and disrupted villi with little goblet cell activity. No significant (P<0.05) effect on feed cost due to addition of phytase and/or NSP enzymes to BD was observed. The cost of feed to produce dozen eggs was comparable among SD, BD and BD supplemented with NSP enzymes and phytase. Key words: Egg quality, Gut conditions, NSP enzymes, Nutrient retention, Phytase, Viscosity. I. Introduction: In recent years there has been a concerted effort to improve the nutritive value of feedstuffs by using exogenous enzymes. On the basis of many publications it may be concluded that the nutritional and economic value of corn, soybean meal (SBM) and other ingredients commonly used in poultry diets in India can be improved by the addition of suitable combinations of NSP enzymes and phytase. An increase in the productive value with enzyme supplementation can be nutrient encapsulating effect of the cell walls and therefore improved energy and amino acid achieved by: (1) release of available phosphorus from phytate hydrolysis, (2) elimination of carbohydrate-protein linkages and therefore improved availability of amino acids, and (3) solubilization of cell wall, non-starch polysaccharides (NSP) for more effective hindgut fermentation and improved overall energy utilization, (4) hydrolysis of certain types of anti-nutritive properties of certain dietary components, including NSP, by their enzymatic hydrolysis to the prebiotic type components which, in turn, may facilitate gut development and health in young chickens. The use of phytase in poultry diets has become widespread because it reduces the P content of manure and can replace inorganic P in feed, thereby reducing P excretion and feed cost. Research on the effect of phytase in broiler diets has been extensive [1]; [2]; [3] where as research on the effect of phytase in layer diets has been less [4]; [5]; [6]; [7]. [8] Reported that commercial phytase increases the release of phytate P from various feedstuffs fed to layers and broilers from between 23 and 34.9% to between 46.8 and 72.4%, respectively. Interactions have been found between xylanase and phytase used in broiler diets [9]; [10]; [11], with phytase affecting the intestinal viscosity and xylanase affecting P availability. However, information on the effect of combining phytase and NSP enzymes on performance and nutrient digestibility in poultry has not been traced. An attempt has been made to explore the additive effect of NSP enzymes and phytase singly or in combination to low energy layer diets. II. Materials and Methods 2.1. Experimental birds and diets The study was conducted at All India Co-ordinated Research Project (AICRP) on Poultry breeding Hyderabad on one hundred and fifty layers (40 weeks) of uniform body weight and production to asses the